Larry, Barry, My last response comes across harsher than I intended. There are likely other reasons besides fire contributing to the poor soils in the pine barrens. Pitch Pine is able to grown in these poorer soil conditions. What I was trying to do was to consider the role of fire in the barrens. With other factors seeming similar and the age of the most stunted trees similar to those in the surrounding area, I was arguing that the intensity of fire was the cause for the more severe stunting. Marion Brooks is an example of the effects of severe fire on a standard forest system and the results are similar to what is being exhibited here, both in terms of the different degrees of stunting of trees in different areas and the paucity of species diversity. The Marion Brooks fires were the result of the aftermath of logging operations. It could be wrong but I still think that given the logging that has taken place in the barrens, that the greater intensity of fire that I am postulating could also have been the result of the aftermath of logging.
I am wondering if you know, or if anybody knows, if after repeated generations of growth under these conditions, if there is some genetic dwarfing taking place or is it purely because of growing conditions? The idea is not Lamarckian selection. It is like the loss of eyes in blind cave fish. They are did not lose because the eyes are useless in the dark, they lost their eyes because it is more energy efficient to not grow them when they do not provide a benefit. In the case of the pines, perhaps it is more efficient in some ways to not try to grow full sized trees, therefore those that are predisposed to have a small size have been selected for resulting in a degree of dwarfism? Ed http://nature-web-network.blogspot.com/ http://primalforests.ning.com/ http://www.facebook.com/profile.php?ref=profile&id=709156957 ----- Original Message ----- From: Edward Frank To: [email protected] Sent: Sunday, January 10, 2010 12:14 AM Subject: Re: [ENTS] Beautiful stunted Pitch Pines Larry, They are similar because in these pitch pine communities are natural fires that mess with the soil structure, while at Marion Brook there was a condition created by timbering that enabled a severe fire to take place. Pitch Pine communities in general are fire dependant systems. Without the fires the pitch pines are displaced by other less fire tolerant species. Whether or not this particular small patch in the pine barrens has lousy soil because of natural burning or because of human caused situation, the soil is still lousy because of burning. You can't deny that the area has been logged. If one area is dramatically different in size in one small patch than it is in adjacent areas, it is not unreasonable that this area was affected by fires of greater intensity than the surrounding areas, or affected more recently. There is no other good explanation for this particular patch to be more stunted than are the trees in adjacent areas given the same basic geology and water conditions. You can't dismiss the idea that this was related to human activity, just because the pine community also burns naturally. Most certainly the analogy is valid and there are similarities between the two areas. That is how you examine question by contrasting and comparing areas with similar but not identical situations. Edward Frank http://nature-web-network.blogspot.com/ http://primalforests.ning.com/ http://www.facebook.com/profile.php?ref=profile&id=709156957 ----- Original Message ----- From: x To: [email protected] Sent: Saturday, January 09, 2010 11:46 PM Subject: Re: [ENTS] Beautiful stunted Pitch Pines most of that area has naturally poor sandy soils and has naturally burned for centuries on top of that, it had stunted growth at the time of the first new European settlers arrival in some areas down there no trees grows above 4-5' or so and even in an average area they are always stunted to some extent over large portions of the region it's one of the very few totally natural stunted pitch pine areas, it's nothing at all like Marion Brooks -Larry From: Edward Frank Sent: Saturday, January 09, 2010 11:13 PM To: [email protected] Subject: Re: [ENTS] Beautiful stunted Pitch Pines Barry, Do you think the smaller stunted trees are similar in age to the larger ones nearby? Sometimes stunting is because of high acidity or some exotic mineral formed from the weathering of the bedrock. There should not be that drastic of a difference geologically in this location to cause the stunting. In this location, I do not think they are stunted because of lack of water. From the setting it looks as if they would not need to develop very long roots to reach water - so that is not a likely explanation. The best suggestion I can make is that this particular area had been subject to a severe fire, maybe from a big brush pile after logging or just brush itself that grew after logging. If the fire is severe enough it will destroy the organic components of the soil and the soil structure leaving behind a mineral soil that will not support many plant species. These are first occupied by some pioneering species, but it will take decades to a couple hundred years before the soil rebuilds enough to support "normal" vegetation. This is what happened at Marion Brooks Natural Area in central Pennsylvania. After eighty or ninety years there are still large section that only are growing blueberries and bracken fern. What trees that are present in the worst hit areas are paper birch and to a lesser extent pitch pine. In your area of the pine barrens the succession is likely first some of the lichens and hedges, then perhaps the pitch pines. But just because they will sprout there does not mean they will grow well. The trees in these areas are typically stunted by the poor nutrients and nature of the soil. I think that is what is happening here. These trees are stunted because they are growing in an area particularly hard hit by fires that ruined the soil structure. Ed http://nature-web-network.blogspot.com/ http://primalforests.ning.com/ http://www.facebook.com/profile.php?ref=profile&id=709156957
